replace env_logger w/ syslog & log_panic

this is due to output as documented in following github issue:
rusterlium/rustler#335

currently uses USER syslog facility

Cargo.toml

@@ -16,4 +16,5 @@ rustler = "0.22.0"
 once_cell = "1.8.0"
 cc_mt = { git = "https://github.com/jrmuizel/cc-mt" }
 log = "0.4.14"
-env_logger = "0.9.0"
+syslog = "^4.0"
+log-panics = "2.0.0"

rs_src/lib.rs

@@ -1,10 +1,15 @@
 mod schema;
 mod ebqn;
 use rustler::{Env,Term};
+use syslog::{Facility, Error};
+extern crate log_panics;
 
 pub fn load(env: Env, _info: Term) -> bool {
     rustler::resource!(schema::Env, env);
-    env_logger::init();
+    syslog::init(Facility::LOG_USER,
+                 log::LevelFilter::Debug,
+                 Some("ebqn"));
+    log_panics::init();
     true
 }
 rustler::init!("ebqn", [ebqn::init_st,ebqn::tests],load=load);